Manual telephone exchange



31, 19-40. W. KLENK ETAL 2,225,725

7 MANUAL TELEPHONE EXCHANGE Filed Jan. 18, 1939 5 Sheets-Sheet 1 DBQ 1940- w. KLENK ErAL 2,226,725

. MANUAL TELEPHONE EXCHANGE Filed'Jan. 18, 1939 3 SheetS -Sheet 2 Filed Jan. 18, 1959 3 Sheets-Sheet 3 Eric/1 56%? V my;

Patented Dec. 31, 1940 UNITED sTATEs Trice TENT" MANUAL TELEPHONEEIXCHANGE Application January 18, 1939, Serial No. 251,538 In Germany January 17, 1938 9 Claims.

The invention relates to cordless manual exchange equipments for telephone systems or the like and has for its object to improve the manufacture of these equipments and to reduce the cost thereof. To such end the invention mainly aims to simplify the jack multiple of such devices.

With these objects in view the invention consists in certain features of novelty which will appear from the following description, reference being had to the accompanying drawings, in which Fig. 1 shows an example of a circuit arrangement suitable for exchange devices as provided 15 by the invention. Fig. 2 is a front elevation of one embodiment of such devices. Fig. 3 is a fragmentary plan of this embodiment. Fig. .4 shows a section on line 44 of Fig. 2. Figs..5 and 6 are fragmentary representations of two 20 plates used for assembling a grid-shaped structure more fully referred to hereafter. Fig. '7, .drawn to a larger scale than Fig. 2, shows a section on line l--1 thereof. Fig. 8 is a'fragmentary front elevation representing a second embodi- 5 ment of the invention. Fig. 9 shows a section on line 99 of Fig. 8, Fig. 10 a partial section on line -ll0 of Fig. 9. Fig. 11 represents one 7 of the contact strips used in the arrangement to which Figs. 9 and 10refer. Fig. 12 illustrates in 30 perspective a slight modification of the jack shown in Figs. 9 and 10. Fig. 13 is a fragmentary perspective view of two contact strips intended for jacks constructed in accordance with Fig. 12.

Fig. 14 illustrates in perspective a plug suitable 35 for jacks of the latter kind. Fig, 15 represents a section on line l-l5 of Fig. 14.

The arrangement shown in Fig. 1 comprises rest jacks P, answering jacks Q, and junction jacks R. Terminals aI, bI aX, bX of lines 4 3 are for the junction of the subscribers stations designated I to X. One pair of lines 3 has terminals a0, 170 for the connection of an office 0-,for instance. By KO, KI KX drop indicators of well known type are denoted, which have make contacts 700, kI kX. W indicates a ringer whose circuit contains lines Ll, L2 in bridge of which the contacts 700, 761 kX are connected. SO, SI SX denote plugs, shown to be inserted in the jacks P and adapted 50 to be inserted in any of the jacks Q, R in order to join the lines 3 to lines 3' arranged at right angles to the'former. By J the operators magneto is designated. Drop indicators KI KX', havingeach a make contact 701' kX, 55 are in well known manner under the control of the subscribers magnetos. Each of the jacks P, Q, R has foursprings p, q, r, respectively, adapted to contact in pairs with two metal rings l3, M with which each of the said plugs is provided.

If subscriber I desires a connection to be estab- T5 lished he removes his handset and actuates his magneto, whereby indicator KI drops its armature or flap, thus closing contact kI. The following circuit is established thereby: LI, kI, L2, W, The operator's ringer W is hence actuated. The dropped flap indicates to the operator who of the subscribers-is calling. The operator then restores indicator KI to normal, withdraws plug SI from that jack P which belongs to the subscribers station I'and inserts this plug in that answering jack Q which is joined to the same lines 3, aI and '3, M as the said jack P.

By restoring the indicator KI to normal, contact 701 is opened, thus disconnecting the ringer W. The operator by means of her telephone now en- 0 quires the calling subscriber as to his wish. If he desired to speak to subscriber X, for instance, the operator removes plug SI from jack Q in order to insert it inone of those jacks R whose lines 3' Y are not busy and which are joined to the lines 3,

a1 and 3, 221. She then removes plug SX from jack P allotted to station X and inserts this plug in jack Q joined to the lines 3, aX and 3, bX. The operator now calls subscriber X by means of her magneto J. If he answers, plug SX is insorted in that jack R. which is joined to the lines 3, (TX and 3, bX' and joined also to the same lines 3' with which the aforesaid jack R has been connected. The stations I, X have thus become interconnected.

At the end of the conversation one of the subscribers will actuate his magneto thus causing the indicator belonging to those lines 3' which have been engaged in the manner just described, such as indicator IQ, for instance, to drop its '40 flap or armature, whereby contact lcI closes a circuit for ringer W. I The operator thereby knows that the conversation has been finished. She therefore restores thisfiap to normal and also withdraws the plugs SI, SK from the said jacks R in order to insert them againin the. respective jacks P.

The circuit arrangement represented in Fig. 1 may be constructed in the manner now explained with reference to Figs. 2 to 7. The jacks P, Q, R 60 are here formed as cavities of a grid-shaped structure B composed of insulating plates 2, 2' carrying the contact springs p, q, 1' shown also in Fig. 1. The plates 2 have slots '0 in which the plates 2' are inserted. Equally, the plates 2' are provided with slots 0' in which the plates 2 are seated, as will be seen from Fig. '7. The springs p, q, r are secured to the plates 2, 2 by rivets 4, for example. The springs 12 are in part separate from one another, as is required in the arrangement disclosed in Fig. 1. The springs q, r are projections of the contact strips 3, 3'. All these springs reach into the cavities of the structure B through apertures 29 provided in the plates 2, 2.

In the embodiment shown in Figs. 8 to 11 the jacks P, Q, R each comprise an insulating socket 8 and the contact springs 1 q, 1', respectively. The sockets 8 are mounted in aboard .l0. The contact strips that correspond to the strips 3, 3', Fig. 2, are designated 3a, 3a. In distinction from the strips 3, 3' the strips 3a, 3a! are each provided with two springs q or r for each jack, as will appear from Fig. 11. Strip 3a here shown has circular openings 35 from the edge of which the springs q or 1', as the case may be, are bent outward. The strips 3a, only represented in Figs. 9 and 10, are of the same construction'as the strips 3a. The openings 35 serve to insert the strips 3a, 3a over the sockets 8. The strips 3a are in this way arranged at right angles to the strips 3a and are separated fromeach other by insulating discs or bushes 3|]. The jack springs, such as springs q shown in Fig. 9, project through slots ll of the sockets 8. The parts 3a, 3a, 30 are held in place by insulating hooks l1 fixed to the sockets 8 by means of a screw [8 each. The hoods I! are dust-proof and humidity-proof.

The plugs suitable for the arrangement shown in Figs. 8 to 11 may be the same as the plugs SO, SI .SX, Fig. 1.

As illustrated in Fig. 12, the jack sockets, here designated 8, may be rectangular in cross section, the strips 3a, 3a. having rectangular openings 35 in lieu of the circular openings 35 shown in Fig. 11. In distinction from the construction represented in Figs. 9, 10, 11 the strips 3a, 3a. each have merely one spring q concerned in the ,formation of each jackQ, or, in the case of the jacks R, Fig. 1, merely one jack spring 1, the arrangement being in this regard similar to that illustrated in Figs, 2 to 7.

The plugs S adapted for use in connection with jacks 8' are rectangular in cross-section.

as shown in Fig. 14. The plug here represented by way of example has four contact pieces or segments 25, 26 instead of the contact rings I3, I4 of the plugs shown in Fig. 1. This plug in the case of a double jack enables, four circuits to be switched jointly.

In all the constructions here disclosed the plugs are guided by jack springs arranged in pairs to oppose each other, whereby a perfect contact effect is insured while the plugs are prevented frorn slanting.

What is claimed is:

1. A telephone exchange comprising a plurality of pairs of fiat metal strips disposed alongside each other and substantially parallel, a second plurality of pairs of flat metal strips disposed alongside each other substantially parallel to one another and crossing said first plurality of pairs of strips, a first plurality of resilient lugs at least one per pair of strips of said second plurality formed integrally from each strip of said first plurality, a second plurality of resilient lugs at least one per pair of strips of said first plurality formed integrally from each strip of said second plurality, an insulating structure carrying said metal strips and forming openings for the insertion of contact plugs, at least one lug of said first plurality of lugs and at least one lug of said second plurality of lugs extending into each of said openings, and a plurality of contact plugs shaped for insertion in said openings and comprising conductive members for interconnecting said lugs.

2. A telephone exchange according to claim 1, wherein the said structure is grid-shaped and composed of a set of insulating plates provided with-slots and another set of insulatingplates likewise fitted with slots, the plates of each such set being seated in the slots of the other set.

3.'A telephone exchange according to claim 1, wherein the said structure is grid-shaped and composed of insulating plates carrying the said fiat metal strips and lugs, these lugs reaching through said plates into the spaces therebetween.

4. A telephone exchange according to claim 1, wherein the said structure comprises a board and jack sockets mounted therein, such sockets carrying the said fiat metal strips and lugs.

5. A telephone exchange according to claim 1, wherein the said structure comprises a board and jack sockets mounted therein, such sockets being of insulating material and carrying the said fiat metal strips and lugs.

6. A telephone exchange according to claim 1,

wherein thesaid structure comprises a board and insulating jack sockets mounted therein and carrying the said flat metal strips and lugs, such sockets having slots for these lugs to project into the interior thereof. 7. A telephone exchange according to claim 1, in which the said structure comprises a board and jack sockets mounted therein, such sockets carrying the said flat metal strips and lugs and having slots through which these lugs reach into the interior of these sockets and a tightly fitting hood at the rear end of each such jack.

8. A telephone exchange according to claim 1, in which-the said structure comprises a board and jack sockets mounted therein and carrying the said flat metal strips'and lugs, such sockets and said plugs being of oblong rectangular crosssection.

9. A telephone exchange according to claim 1, in which the said structure comprises .a board and jack sockets mounted therein and carrying the said fiat metal strips and lugs, these sockets and said plugs being of oblong rectangular cross-section, each plug comprising an insulating body and contact segments provided therein.

' WILFRIED KLENK.

ERICH BEHM. 

